Radiator replacement

[slotard]

My truck seems to be losing some coolant, and I saw a wet spot on the rear of the radiator so that appears to be the problem.

It's a 350, but there's some chance I'll swap in a 5.3 or 6.0 sometime down the road. I'm happy enough with brass or aluminum but don't want any plastic on it, I've had too many problems with radiators with plastic end caps.

Am I better off buying one from a junkyard or is there a reasonably priced aluminum option I should look at? Thanks for any advice.